Siemens TCA785 Datasheet

TCA 785

Phase Control IC TCA 785

Bipolar IC

Features

● Reliable recognition of zero passage

● Large application scope

● May be used as zero point switch

● LSL compatible

● Three-phase operation possible (3 ICs)

● Output current 250 mA

● Large ramp current range

● Wide temperature range

Type Ordering Code Package

P-DIP-16-1

TCA 785 Q67000-A2321 P-DIP-16-1

This phase control IC is intended to control thyristors, triacs, and transistors. The trigger pulses
can be shifted within a phase angle between 0 ˚ and 180 ˚. Typical applications include
converter circuits, AC controllers and three-phase current controllers.

This IC replaces the previous types TCA 780 and TCA 780 D.

Pin Definitions and Functions
Pin Symbol Function

1 GND Ground
2

3
4

5 V
6

7
8 V

Q2
Q U
Q2

SYNC Synchronous voltage

I
Q Z

REF Stabilized voltage

Output 2 inverted
Output U
Output 1 inverted

Inhibit
Output Z

Pin Configuration

(top view)

Semiconductor Group 1

9
10

R

9

C10

Ramp resistance

Ramp capacitance
11 V11 Control voltage
12 C

12 Pulse extension

13 L Long pulse
14

15
16 V

Q 1
Q 2

S Supply voltage

Output 1

Output 2

09.94

TCA 785

Functional Description

The synchronization signal is obtained via a high-ohmic resistance from the line voltage
(voltage V
synchronization register.

This synchronization register controls a ramp generator, the capacitor C
by a constant current (determined by R

11 (triggering angle ϕ), a signal is processed to the logic. Dependent on the magnitude of the

V

control voltage V
For every half wave, a positive pulse of approx. 30

Q 2. The pulse duration can be prolonged up to 180˚ via a capacitor C
to ground, pulses with a duration between

Outputs and supply the inverse signals of Q 1 and Q 2.
A signal of
A signal whichcorresponds to theNOR linkof Q 1 and Q 2 is available at output Q Z(pin 7).
The inhibit input can be used to disable outputs Q1, Q2 and , .
Pin 13 can be used to extend the outputs and to full pulse length (180˚ –

5). A zero voltage detector evaluates the zero passages and transfers them to the

10 of which is charged

9). If the ramp voltage V10 exceeds the control voltage

11, the triggering angle ϕ can be shifted within a phase angle of 0˚ to 180˚.

µs duration appears at the outputs Q 1 and

12. If pin 12 is connected

ϕ and 180˚ will result.

Q 1 Q 2

ϕ +180˚ which can be used for controlling an external logic,is available at pin 3.

Q 1 Q 2

Q 1 Q 2

ϕ).

Block Diagram

Semiconductor Group 2

TCA 785

Pulse Diagram

Semiconductor Group 3

Absolute Maximum Ratings

TCA 785

Inhibit voltage
Control voltage
Voltage short-pulse circuit

Junction temperature
Storage temperature

Thermal resistance
system - air R

Operating Range

Limit Values

min. max.

S – 0.5 18

Q – 10 400

6

V
V11
V13

Q VS

Q VS

Tj
Tstg – 55

th SA 80

– 0.5
– 0.5
– 0.5

V
VS
VS

150
125

UnitParameter Symbol

VSupply voltage V
mAOutput current at pin 14, 15 I

S

V
V
V

µASynchronization input current V5 – 200 ± 200

VOutput voltage at pin 14, 15 V
mAOutput current at pin 2, 3, 4, 7 IQ 10
VOutput voltage at pin 2, 3, 4, 7 V
˚C

˚C

K/W

Characteristics

≤ VS ≤ 18 V; – 25 ˚C ≤ TA ≤ 85 ˚C; f = 50 Hz

8

IS 4.5 16.5 10

S1 … S6 open

11 = 0 V

V

10 = 47 nF; R 9 = 100 kΩ

C

Synchronization pin 5
Input current

2 varied

R

Offset voltage

5 rms

I

∆V5

A – 25 85

Limit Values Test

min. max.

typ.

UnitParameter Symbol

mASupply current consumption

30 1

200
75

µA

mV

VSupply voltage VS 818
HzOperating frequency f 10 500
˚CAmbient temperature T

Circuit

430

Control input pin 11
Control voltage range
Input resistance

V
R11

11

0.2 1

Semiconductor Group 4

V10 peak

V
k

Ω

515

Characteristics (cont’d)

≤ VS ≤ 18 V; – 25 ˚C ≤ TA ≤ 85 ˚C; f = 50 Hz

8

TCA 785

Ramp generator
Charge current
Max. ramp voltage
Saturation voltage at capacitor
Ramp resistance
Sawtooth return time

Inhibit pin 6
switch-over of pin 7
Outputs disabled
Outputs enabled
Signal transition time
Input current

6 = 8 V

V

Input current

6 = 1.7 V

V
Deviation of I10

R 9 = const.

S = 12 V; C10 = 47 nF

V

Deviation of I

10

R 9 = const.

S = 8 V to 18 V

V

Deviation of the ramp voltage
between 2 following
half-waves, V

S = const.

10

I
V10
V10
R9
tf

V6 L
V6 H
tr
I6 H

– I6L

10

I

I10

∆V10 max

Limit Values Test

min. max.

10
100

3

typ.

225

1000

2 – 2

V

350
300

80

4
1

80

– 5

– 20

3.3

3.3
500
150

± 1

2.5
5

800
200

5

20

UnitParameter Symbol

µA

V
mV

Ω

k

µs

V
V

µs
µA

µA

%

%

%

Circuit

1

1.6
1
1

1
1
1
1

1

1

1

Long pulse switch-over
pin 13
switch-over of S8
Short pulse at output
Long pulse at output
Input current

13 = 8 V

V

Input current

13 = 1.7 V

V

13 H

V
V13 L
I13 H

– I13 L

3.5

45

Outputs pin 2, 3, 4, 7
Reverse current

Q = VS

V

Saturation voltage

Q = 2 mA

I

ICEO
Vsat 0.1

Semiconductor Group 5

2.5

2.5

65

2
10

100

10
2

V
V

µA
µA

µA

V

1
1
1

1

2.6

2.60.4